Move sync notifier contruction out of syncer thread.

chrome/browser/sync/engine/syncapi.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file defines the "sync API", an interface to the syncer
 // backend that exposes (1) the core functionality of maintaining a consistent
 // local snapshot of a hierarchical object set; (2) a means to transactionally
 // access and modify those objects; (3) a means to control client/server
 // synchronization tasks, namely: pushing local object modifications to a
 // server, pulling nonlocal object modifications from a server to this client,
@@ skipping 828 matching lines @@
   // backend state. Initialization will open the database, or create it if it
   // does not already exist. Returns false on failure.
   // |sync_server_and_path| and |sync_server_port| represent the Chrome sync
   // server to use, and |use_ssl| specifies whether to communicate securely;
   // the default is false.
   // |post_factory| will be owned internally and used to create
   // instances of an HttpPostProvider.
   // |model_safe_worker| ownership is given to the SyncManager.
   // |user_agent| is a 7-bit ASCII string suitable for use as the User-Agent
   // HTTP header. Used internally when collecting stats to classify clients.
-  // |sync_notifier| will be owned internally and used to listen for
-  // notifications.
+  // |sync_notifier| used to listen for notifications, not owned.
   bool Init(const FilePath& database_location,
             const char* sync_server_and_path,
             int sync_server_port,
             bool use_ssl,
             HttpPostProviderFactory* post_factory,
             browser_sync::ModelSafeWorkerRegistrar* registrar,
             const char* user_agent,
             const SyncCredentials& credentials,
             sync_notifier::SyncNotifier* sync_notifier,
             const std::string& restored_key_for_bootstrapping,
@@ skipping 218 matching lines @@
   virtual const std::string GetResponseHeaderValue(
       const std::string& name) const = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(HttpPostProviderInterface);
 };
 
 }  // namespace sync_api
 
 #endif  // CHROME_BROWSER_SYNC_ENGINE_SYNCAPI_H_